1. Field of the Invention
The present invention relates to an operation method for controlling access attributes of a memorized page of a memory and its structure, and more particularly, to an attribute configuration for controlling operation of the memorized page, making the memorized page no more comprehensively receive the storage data from CPU or hard disk, but further control and manage the data flow to provide system safety as a common protective design.
2. Description of the Prior Art
Whereas, dynamic random access memory (hereinafter referred to as DRAM) appears in the form of memorized page; that is, DRAM is composed of continuous memorized pages or continuous storage cells, for example, the size of each memorized page is 4 K Bytes, then 16 M DRAM can be divided into 4000 units of memorized pages (000xcx9cFFF) of the size of 4 K.
CPU performs the read/write control to DRAM through the chipset. The data intended to execute in a hard disk shall be written into DRAM first, then CPU shall read the data from DRAM for processing, or after the data processing performed by CPU, the processed data shall be written into DRAM, and then the hard disk will read data back from DRAM. The operation of DRAM storage is counted in memorized page. In other words, concerning the system operation of a computer in general, DRAM provides basic actions of data storage and retrieval.
As the world has gradually progressed towards computerization and digitalization, many commercial behaviors have turned to information technology application. While enjoying the efficiency, convenience and commercial opportunity brought by Internet and Intranet, computer and network safety has been gradually concerned. On the other hand, concerning computer crime, no matter in terms of technology, revision level or amount of crime, all show the tendency of skill improving and amount increasing. Therefore, most people select cryptographic system for protecting their important data. However, no matter whichever cryptographic system, the public key, the private key, or the password of the system itself or set additionally, after the cryptographic system is started, it shall be loaded in DRAM and then checked. Since DRAM is a necessary passing device of system data, and it can only receive the data conveyed from CPU or hard disk without selecting, therefore, no matter legal service of DRAM (system itself) or through intrusion of external party, all data can be easily accessed and revised. For example, a hacker may intrude into DRAM to retrieve the public key, private key and password data of the cryptographic system to change the check operation to check approval or no operation through some software (such as soft ICE), and the system can be easily accessed.
Furthermore, as the virus in a floppy disk or a optical disk is loaded into DRAM, through execution of CPU to damage or revise the important parameter in a system, these parameters may cause such influences as the configuration of memory in DRAM, the division of disk driver and the access authority of a user in using the system, etc. and make the system shut down, be damaged or unable to work normally or function in an abnormal manner. The general anti-virus programs work through comparing the virus code in a floppy disk or DVD, once the user fails to update it in time, some unknown viruses still get chances to access to DRAM and make the system shut down through execution of CPU, thus the virus written into DRAM cannot be prevented, therefore, effective prevention method still cannot be provided.
In view of this, the major object of this invention is to provide a kind of operation method for controlling access attributes of a memorized page of a memory, in particular to provide a control method for low-level driver or system chipset to perform read/write operation to partial areas of the memory, mainly by means of using register configuration procedure to perform the operable region configuration of the memory, and by means of practical operation procedure to confirm the operation mode of the said region, to further control the said region for read-only, write-only, write-once, read-once, etc., to ensure the data loaded in the memory, which include the program which will be executed and the password which will be checked, etc., to be free from the intrusion from hackers, viruses, etc., and to provide a common protection for system safety.
It is another object of the present invention is to provide a common protection for system safety to ensure the data loaded in the memory, which include the program which will be executed and the password which will be checked, etc., to be free from the intrusion from hackers, viruses, etc.